Copper porphyrin-catalyzed C(sp2) ? O bond construction via coupling phenols with formamides

Copper porphyrin-catalyzed construction of C(sp(2))-O bond via coupling formamides with phenols was achieved firstly. A broad range of substrates afforded various carbamates in moderate to good yields with good functional group tolerance at low catalyst loading. Intermolecular competing kinetic isotope effect experiment indicated that the generation of formamide radical is the rate-determining step of current cross-dehydrogenative coupling (CDC) reaction. The research extends the application of metalloporphyrin in CDC reaction.